/* ESPRESSIF MIT License
 * 
 * Copyright (c) 2018 <ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD>
 * 
 * Permission is hereby granted for use on all ESPRESSIF SYSTEMS products, in which case,
 * it is free of charge, to any person obtaining a copy of this software and associated
 * documentation files (the "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished
 * to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event_loop.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "sdkconfig.h"

#include "lwip/err.h"
#include "lwip/sys.h"

#include "mdns.h"

/* The examples use WiFi configuration that you can set via 'make menuconfig'.

   If you'd rather not, just change the below entries to strings with
   the config you want - ie #define EXAMPLE_WIFI_SSID "mywifissid"
*/
#define EXAMPLE_ESP_WIFI_SSID CONFIG_ESP_WIFI_SSID
#define EXAMPLE_ESP_WIFI_PASS CONFIG_ESP_WIFI_PASSWORD
#define EXAMPLE_ESP_MAXIMUM_RETRY CONFIG_ESP_MAXIMUM_RETRY
#define EXAMPLE_ESP_WIFI_AP_SSID CONFIG_ESP_WIFI_AP_SSID
#define EXAMPLE_ESP_WIFI_AP_PASS CONFIG_ESP_WIFI_AP_PASSWORD
#define EXAMPLE_MAX_STA_CONN CONFIG_MAX_STA_CONN
#define EXAMPLE_IP_ADDR CONFIG_SERVER_IP
#define EXAMPLE_ESP_WIFI_AP_CHANNEL CONFIG_ESP_WIFI_AP_CHANNEL

static const char *TAG = "camera wifi";

static int s_retry_num = 0;

static esp_err_t event_handler(void *ctx, system_event_t *event)
{
    switch (event->event_id)
    {
    case SYSTEM_EVENT_AP_STACONNECTED:
        ESP_LOGI(TAG, "station:" MACSTR " join, AID=%d",
                 MAC2STR(event->event_info.sta_connected.mac),
                 event->event_info.sta_connected.aid);
        break;
    case SYSTEM_EVENT_AP_STADISCONNECTED:
        ESP_LOGI(TAG, "station:" MACSTR "leave, AID=%d",
                 MAC2STR(event->event_info.sta_disconnected.mac),
                 event->event_info.sta_disconnected.aid);
        break;
    case SYSTEM_EVENT_STA_START:
        esp_wifi_connect();
        break;
    case SYSTEM_EVENT_STA_GOT_IP:
        ESP_LOGI(TAG, "got ip:%s",
                 ip4addr_ntoa(&event->event_info.got_ip.ip_info.ip));
        s_retry_num = 0;
        break;
    case SYSTEM_EVENT_STA_DISCONNECTED:
    {
        if (s_retry_num < EXAMPLE_ESP_MAXIMUM_RETRY)
        {
            esp_wifi_connect();
            s_retry_num++;
            ESP_LOGI(TAG, "retry to connect to the AP");
        }
        ESP_LOGI(TAG, "connect to the AP fail");
        break;
    }
    default:
        break;
    }
    mdns_handle_system_event(ctx, event);
    return ESP_OK;
}

void wifi_init_softap()
{
    if (strcmp(EXAMPLE_IP_ADDR, "192.168.4.1"))
    {
        int a, b, c, d;
        sscanf(EXAMPLE_IP_ADDR, "%d.%d.%d.%d", &a, &b, &c, &d);
        tcpip_adapter_ip_info_t ip_info;
        IP4_ADDR(&ip_info.ip, a, b, c, d);
        IP4_ADDR(&ip_info.gw, a, b, c, d);
        IP4_ADDR(&ip_info.netmask, 255, 255, 255, 0);
        ESP_ERROR_CHECK(tcpip_adapter_dhcps_stop(WIFI_IF_AP));
        ESP_ERROR_CHECK(tcpip_adapter_set_ip_info(WIFI_IF_AP, &ip_info));
        ESP_ERROR_CHECK(tcpip_adapter_dhcps_start(WIFI_IF_AP));
    }
    wifi_config_t wifi_config;
    memset(&wifi_config, 0, sizeof(wifi_config_t));
    snprintf((char *)wifi_config.ap.ssid, 32, "%s", EXAMPLE_ESP_WIFI_AP_SSID);
    wifi_config.ap.ssid_len = strlen((char *)wifi_config.ap.ssid);
    snprintf((char *)wifi_config.ap.password, 64, "%s", EXAMPLE_ESP_WIFI_AP_PASS);
    wifi_config.ap.max_connection = EXAMPLE_MAX_STA_CONN;
    wifi_config.ap.authmode = WIFI_AUTH_WPA_WPA2_PSK;
    if (strlen(EXAMPLE_ESP_WIFI_AP_PASS) == 0)
    {
        wifi_config.ap.authmode = WIFI_AUTH_OPEN;
    }
    if (strlen(EXAMPLE_ESP_WIFI_AP_CHANNEL))
    {
        int channel;
        sscanf(EXAMPLE_ESP_WIFI_AP_CHANNEL, "%d", &channel);
        wifi_config.ap.channel = channel;
    }

    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_AP, &wifi_config));

    ESP_LOGI(TAG, "wifi_init_softap finished.SSID:%s password:%s",
             EXAMPLE_ESP_WIFI_AP_SSID, EXAMPLE_ESP_WIFI_AP_PASS);
}

void wifi_init_sta()
{
    wifi_config_t wifi_config;
    memset(&wifi_config, 0, sizeof(wifi_config_t));
    snprintf((char *)wifi_config.sta.ssid, 32, "%s", EXAMPLE_ESP_WIFI_SSID);
    snprintf((char *)wifi_config.sta.password, 64, "%s", EXAMPLE_ESP_WIFI_PASS);

    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config));

    ESP_LOGI(TAG, "wifi_init_sta finished.");
    ESP_LOGI(TAG, "connect to ap SSID:%s password:%s",
             EXAMPLE_ESP_WIFI_SSID, EXAMPLE_ESP_WIFI_PASS);
}

void app_wifi_main()
{
    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    wifi_mode_t mode = WIFI_MODE_NULL;

    if (strlen(EXAMPLE_ESP_WIFI_AP_SSID) && strlen(EXAMPLE_ESP_WIFI_SSID))
    {
        mode = WIFI_MODE_APSTA;
    }
    else if (strlen(EXAMPLE_ESP_WIFI_AP_SSID))
    {
        mode = WIFI_MODE_AP;
    }
    else if (strlen(EXAMPLE_ESP_WIFI_SSID))
    {
        mode = WIFI_MODE_STA;
    }

    esp_err_t ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND)
    {
        ESP_ERROR_CHECK(nvs_flash_erase());
        ret = nvs_flash_init();
    }
    ESP_ERROR_CHECK(ret);

    if (mode == WIFI_MODE_NULL)
    {
        ESP_LOGW(TAG, "Neither AP or STA have been configured. WiFi will be off.");
        return;
    }

    tcpip_adapter_init();
    ESP_ERROR_CHECK(esp_event_loop_init(event_handler, NULL));
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
    ESP_ERROR_CHECK(esp_wifi_set_mode(mode));

    if (mode & WIFI_MODE_AP)
    {
        wifi_init_softap();
    }

    if (mode & WIFI_MODE_STA)
    {
        wifi_init_sta();
    }
    ESP_ERROR_CHECK(esp_wifi_start());
    ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE));
}